Definition of rock dust in English:

rock dust

noun

North American
Mining
  • Pulverized rock, especially (in later use) as spread in coal mines in order to reduce the risk of coal-dust explosions.

verb

North American
Mining
  • with object To subject (a coal mine) to rock dusting.

Origin

Early 19th century; earliest use found in American Magazine. From rock + dust<br>early 20th century; earliest use found in Compressed Air Magazine. From rock + dust.

Pronunciation

rock dust

/ˈrɒk dʌst/